Locomotive-boiler



(No Model.)

J. T. MCLBLLAN. LoooMoTIVE BOILBR.

Patented Mar. '7, 1893.

TH: Nunms Firms co. Pnoaufuo.. wAsHmcrcm, ofc,

Uivrrnn STATES FFICEG JOHN T. MCLELLAN, OF TRURO, CANADA, ASSIGNOR OFONE-HALF TO HORACE W. OHALFANT, OF MINNEAPOLIS, MINNESOTA.

LOCOMOTlVE-BOILER.

SPECIFICATION forming part of Letters Patent No. 493,232, dated March 7,1893. Application met February 15, 1892. serial No. 421,571- (Nc model.)

To all whom it may concern,.-

Be it known that I, JOHN T. MCLELLAN, of Truro, in the county ofColchester, Province of Nova Scotia, Canada, have invented certainImprovements in Locomotive-Boilers, of which the following is aspecification.

My invention relates to means for obtaining from a given quantity offuel a greater amount of energy than can be developed in the ordinaryboiler and its object is to materially increase the heating surface ot'the boiler.

To this end my invention consists in the combination with the boilershell, of the crown plate, the dues, the lire-box, the grate, and anintermediate water leg or partition depending from the top of the firebox and having openings in its top, front and rear walls for the inletand egress of water and steam; and in various constructions andcombinations hereinafter described and particularly pointed out in theclaim.

My invention will be more readily understood by reference to theaccompanying drawings, in which:-

Figure 1 is a side elevation of a boiler embodying my invention, thefire-box of the same being shown in vertical section,the section beingtaken through my auxiliary or middle water leg. Fig.l 2 is a frontelevation partly in section on the line y-y of Fig. l.

Fig. 3 is a transverse section on the line -m,

The two doors 17, 17 are hung upon asingle pin or hinge 19 and have theusual fastening latches. The door casings 18 extend through both the endof the shell and the plate 6 into the lire-box.k Midway between thesides of ythe tire-box and extending longitudinally be- The usual waterlegs are formed tween the plates 3 and 6 I arrange the hollow partitionmade up by the doubled plate 11 having its upper edges secured to theunder side of the crown plate. The flared edges 16 of this plate 11 aresecured upon the plate 6. The forward portion of the hollow partition isriveted to the lower part only of the plate 3, the edges 16 thereofbeing firmlyA riveted upon said plate. 'The upper part of this portionof the plate 1l is cut back in front of the dues, the chamber 12 betweenthe plates being closed at this point by the transverse plate 13. Thus aclear space 15 is left in front of the ues for the free use of the tubeexpander from the two sides of the fire-box. A continuous space is left,between the grate and the lower edge of the doubled plate 1l to allowthe removal or rocking of the grate. The water entersthe chamber or leg12 through a large number of openings, 14 arranged in the `plates 3, 8and 6 respectively and communicating with the chamber 12. For clearingout this intermediate or auxiliary leg I provide the opening 20 leadingfrom the lower corner of the leg 12 and extending through therear of theboiler shell, the opening being v closed by the removable plug 2l. Itwill be seen that by removing the plug the wat-er may be drawn oif fromthe leg to flush and clean out all of the sediment which may have accu#mulated therein. By this means I subject a considerable body of water tothe most direct and the greatest heat obtainable from the fuel in thefire box, while at the same time adding but little to the cost of theconstruction ofthe boiler. In addition to this advantage is that ofdividing the cold drafts of air entering through the doors, so that onlyone half of the boiler is cooled when the door is opened, the other halfretaining its full heat. As a result I save the pressure of steam in theboiler and keep the same practically constant.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- The combination, with the crown-plate, of the sidesthereof, the boiler-shell surrounding the same, the grate, water legsbeing formed at the sides of the crown plate and the shell tine-sheet ofthe re-box,snbstantia1ly as deand extending down to the grate, theuescribed. [o sheet and the fines, the intermediate Water In testimonywhereof I have hereunto set leg terminating above the grate and formedmy hand this 10th day of February, 1892.

5 of a separate plate, the transverse part 13 .I OHN T. MCLELLAN.

thereof, an opening 15 being formed between In presence of said plateand the flue-sheet, and perforations F. S. LYON, 14 in the crown-plateand in the end Wall or C. G. I-IAWLEY.

